Prior art J-lay pipelaying vessels are known, wherein the J-lay tower is fixed on the vessel. In other known vessels the J-lay tower is supported on bearing means which allow to pivot the J-lay tower, so that the J-lay tower can be brought in a desired orientation and then held in said orientation. In these type of vessels, the J-lay tower, and thus the pipeline, is subjected to sea-state induced vessel motions. As the vessel often are very large, sometimes semi-submersible vessels, the sea-state induced vessel motions are in many cases not a problem.
A far less generally accepted prior art design is disclosed in U.S. Pat. No. 3,581,506 on which the preamble of claim 1 is based. In said prior art vessel the J-lay tower is gimballed so that a freely pivotal motion in any direction is possible. Roll and pitch of the vessel thus do not result in additional stress in the pipeline. In U.S. Pat. No. 3,851,506 a crane controlled by an operator is proposed for loading a new pipe section in the J-lay tower.